As a crimp terminal, there have been used an open-barrel-type crimp terminal and a closed-barrel-type crimp terminal. The open-barrel-type crimp terminal includes a barrel member which crimps a wire tip formed by peeling off an insulating cover on a distal end side of the insulated wire, the barrel member obtained by bending a material from both sides in the width direction and making edge portions of the both sides face each other in an opposed manner at an intermediate portion. The closed-barrel-type crimp terminal includes a crimping section formed into a hollow shape which allows the insertion of a wire tip into the inside of the crimping section through an insertion opening at a proximal end side.
In the case of the open-barrel-type crimp terminal, the crimping section is exposed under a severe in-use environment and hence, there exists a possibility that a surface of the crimping section and a surface of a conductor in a crimping connecting portion will corrode so that conductivity will be lowered.
In contrast, the closed-barrel-type crimp terminal is formed into a hollow shape and hence, a wire tip inserted into the crimp terminal is covered by the crimp terminal without any gap over the whole circumferential direction. Accordingly, it is considered that the conduction between the crimp terminal and the conductor of the insulated wire can be surely acquired and, at the same time, corrosion which may occur on the surface of the crimping section and on the surface of the conductor in the crimping connecting portion can be prevented.
On the other hand, a wire connection structural body is configured by connecting such a crimp terminal to an insulated wire. That is, the wire tip of the insulated wire is arranged in the crimping section of the crimp terminal and, thereafter, the crimp terminal is crimped to the wire tip by caulking the crimping section using a wire crimping device such as a terminal crimping device disclosed in Patent Document 1, for example.
However, in the case of the closed-barrel-type crimp terminal, to arrange the wire tip of the insulated wire on the crimping section of the crimp terminal, it is necessary to insert the wire tip of the insulated wire from an insertion opening formed on a proximal end side of the crimping section. However, from a viewpoint of water-blocking performance, an outer diameter of the insulated wire and an inner diameter of the crimping section are set substantially equal to each other, that is, these diameters are set such that there is substantially no gap between an outer periphery of an insulating cover section of the wire tip inserted into the crimping section and an inner periphery of the crimping section. Accordingly, the closed-barrel-type crimp terminal has a drawback that the insertion of the wire tip of the insulated wire into the crimp terminal is only possible after aligning the center of the wire tip and the center of the crimping section to each other.